an Excel program created to extract relevant data (from the continuous data collected by the photoacoustic sensor every minute) is used. The same program also calculates the flux of selected gases from the tested surface, using Pedersen's equation (2001).

selected data are copied and pasted as values into a compiled data set

Temperature data: temperature data is collected by temperature probes placed at a 5-, 20-, and 40-cm depth in the animal waste stack and stored in a data logger. Data processing and analysis is conducted according to the following instructions.

Biofilter respiration (Biological Oxygen Demand, BOD), Moisture and Volatile Solids (organic matter) content data: biofilter samples are periodically collected and analyzed in the lab according to the following instructions for BOD and moisture and VS analysis.

Once processed into an compatible format, temperature, BOD, and moisture content data is included in the statistical analysis as both an input affect gaseous flux and and output affected by time and biofilter treatments.